CrackTech (formerly LeetCode-Which-Company) tackles a familiar pain point for anyone prepping for software engineering interviews: knowing which companies have asked which algorithmic problems on LeetCode. What sets it apart isn’t just the tagging, but the dynamic freshness indicator and integrated progress tracking — all wrapped in a privacy-conscious, community-driven browser extension.
what CrackTech does and how it works
At its core, CrackTech is a browser extension available for Chrome and Firefox. It overlays company-specific data onto LeetCode problems, showing you which companies have historically asked those questions in interviews. Instead of relying solely on LeetCode’s own tagging — which can be incomplete or stale — it uses a crowdsourced database that is regularly updated through commits tagged with ‘company-info’.
The extension highlights the five most recent companies associated with a problem, marked with a ✯ to indicate “company freshness.” This turns a static lookup into a dynamic signal of what’s currently relevant in the market.
Beyond just company tags, CrackTech version 2.x brought deeper integration with popular Software Development Engineer (SDE) preparation sheets like Striver, Blind75, and NeetCode. This means it tracks your personal progress on these curated problem sets within the extension, suggesting what to solve next based on difficulty tiers.
Additionally, it curates content beyond just data structures and algorithms, aggregating system design, low-level design, test engineering, and behavioral interview question resources. This makes it more of a centralized interview prep dashboard than just a tagging tool.
Architecturally, the extension operates entirely on the client side as a popup window, intentionally avoiding any data collection to protect user privacy. The company data itself is maintained in a public GitHub repository, updated by contributors worldwide. This approach leverages Git’s version control and the open-source community to keep information fresh without a centralized server.
technical strengths and design tradeoffs
One of the most interesting aspects under the hood is the “company freshness” mechanic. The extension ranks companies by recency using commit metadata, then surfaces the top five with a star marker. Implementing this client-side within a browser extension is a neat tradeoff. It avoids the complexity and cost of a server-side ranking pipeline but means the freshness heuristic relies on the latest static data pulled from the GitHub repo.
This crowdsourced database model is both a strength and a limitation. On the plus side, it benefits from community contributions, often surpassing LeetCode’s own tagging accuracy. It’s transparent and open to corrections and additions. On the downside, it depends on active maintenance of data commits and might lag behind in ultra-real-time updates compared to a proprietary backend.
The extension’s choice to avoid any data collection is a clear privacy win. Many similar premium tools track user behavior to generate recommendations or maintain user profiles. CrackTech sidesteps this by doing all processing client-side, though this limits personalization complexity.
Integrating progress tracking for multiple popular SDE sheets directly into the extension is also a practical feature. It reduces context switching and provides a guided path through widely accepted interview prep roadmaps. However, this integration is limited to those specific sheets and does not allow custom progress tracking.
The curated lists for system design and behavioral interviews supplement algorithmic prep, acknowledging that technical interviews cover more than just coding challenges. This aggregation saves users from hunting multiple resources but also means the extension serves as a content aggregator rather than generating original material.
The extension’s stack is JavaScript, fitting for browser extension development. The codebase is maintained actively with meaningful commits, especially around updating company info. From a code quality perspective, the repo is straightforward, focusing on practical UX and reliable data display rather than complex processing or heavy UI frameworks.
explore the project
Navigating the CrackTech repository, you’ll find the core extension code, the crowdsourced company data in JSON or similar formats, and regular commit history tagged ‘company-info’ to track updates.
The README details the scope of the extension, usage notes, and links to contribute data or report issues. Since there are no installation commands or build scripts extracted in the analysis, the best way to try it is to install the extension directly from the Chrome Web Store or Firefox Add-ons site, where it’s published.
The repo’s wiki or issues section can also offer insight into ongoing development and community discussions about data accuracy and feature requests.
verdict
CrackTech is relevant for anyone seriously preparing for software engineering interviews who wants up-to-date, community-verified company tagging on LeetCode problems without sacrificing privacy.
Its crowdsourced model and freshness signal provide a unique angle compared to premium alternatives, though it requires active community engagement to maintain data quality. The client-side design means you won’t get personalized analytics or behavior-driven recommendations, but that’s a conscious tradeoff for simplicity and privacy.
If you prefer a no-frills, transparent, and open-source tool to augment your interview prep, especially if you follow popular SDE sheets, CrackTech is worth trying. Its curated design and behavioral content aggregation add practical value beyond company tags.
For developers interested in browser extension architecture or community-driven data projects, the repo also offers a clean example of balancing real-time relevance with privacy and open contribution.
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→ GitHub Repo: ssavi-ict/LeetCode-Which-Company ⭐ 159 · JavaScript